Uniformly anchoring Sb2O5 nanoparticles on graphene sheets via Co2+-induced deposition for enhanced lithium/sodium-ion storage

Abstract

Antimony oxides hold great competitive edges for lithium/sodium-ion storage on account of their large theoretical capacities. Compositing antimony oxide particles with conductive supporters can greatly improve electrochemical performance, but composites still suffer from weak interactions, causing unsatisfactory rate capability and cycling stability. Herein, we demonstrate that the interactions between Sb₂O₅ particles and reduced graphene oxide (rGO) sheets are enhanced by a facile Co²⁺-induced deposition strategy that is helpful in boosting the migration of electrons/ions and maintaining structural integrity of electrodes. The results of physical and electrochemical measurements reveal that the presence of Co²⁺ ions effectively boost the uniform anchoring of Sb₂O₅ nanoparticles on rGO sheets with the initial in situ formation of CoSb₂O₆ as nucleation sites, which greatly strengthen the interaction effects between active oxides and conductive rGO. Accordingly, the Co–Sb₂O₅/rGO anode delivers a large reversible lithium-storage capacity of 1027 mA h g⁻¹, high rate capacity of 507.3 mA h g⁻¹, even at 3.0 A g⁻¹, and excellent durability (75.4% capacity retention after 500 cycles at 0.5 A g⁻¹), surpassing most of the reported antimony oxide anodes. Our work shows an efficient strategy to construct ultrafine oxides on oxygenic carbonaceous materials with strengthened structure for high-performance energy storage.